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300 14 Compressive Modulation
minimum Euclidean distance of the constellation could be smaller than noise shift in
a large portion of modulation symbols. For this reason, a receiver adaptation scheme
will have a significantly degraded performance at low channel SNR if it aggressively
uses a very dense constellation.
Mismatched decoding cannot be avoided if the receiver adaptation scheme uses
existing rateless codes, such as LT codes and Raptor codes, because they can only
decode from rateless bits. If there is a rateless encoder that can directly generate
multilevel symbols, and a corresponding decoder that can directly decode from the
multilev ...